Incremental and saving space

I did a complete drive backup so I would be sure it will boot if I have to restore to a new drive. If I know a partition did not change, since the last backup, will the next incremental backup file size be the same if I uncheck that partition? Or doesn't it matter since nothing changed so nothing will be added to the backup file. Seems like something for that drive would be written if it was checked to back it up, even if there wasn't and changes.

If nothing changed, the incremental backup of that drive would be very small. However, there may have been some changes such as last time accessed, etc. even if you didn't save changes to the partition, so it's best to include it in the incrementals. Besides, if there was a change that you forgot, it wouldn't be lost. Better safe than whatever the alternative is.